Single crystals of La2NaTaO6 were grown out of a reactive high-temperature hydroxide melt. The structure was determined by single crystal X-ray diffraction. La2NaTaO6 adopts the monoclinically distorted double perovskite structure type with general formula A(2)BB'O-6, where tantalum atoms are located on the B' site. La2NaTaO6 crystallizes in the monoclinic space group P21/n with a = 5.6904(2) angstrom, b = 5.9824(2) angstrom, c = 8.1423(2) angstrom and beta = 90.8650(10)degrees. An optical bandgap of 4.5 eV was estimated from the UV-vis diffuse reflectance spectrum. (c) 2007 Elsevier B.V. All rights reserved.